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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi chen Lin Lu Xian-Rong Song Mu-jia Luo Qiang Xiao Key Laboratory of Organic Chemistry of jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2.–H functionalization, dearomative 2.3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization

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Structural design of aeroengine radiators:State of the art and perspectives

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Propulsion and Power Research 2024年第3期13卷 319-334页

作者： cheng-Wei Fei chen Li {2.-Yi Lin Yao-{2. Han Yat-Sze Choy Chuan-Hai chen Department of Aeronautics and Astronautics Fudan UniversityShanghai 200433China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong Kong 999077China Key Laboratory of CNC Equipment Reliability Ministry of EducationJilin UniversityChangchun 130015China

Structural modularization,lightweight and functional integration are the urgent devel-opment directions for next generation high-performance *** concentration during aeroengine operation would lead to local high temperature,which tremendously negative impacts on aeroengine structural life and ***,the design and optimization of radiator structures are significant for the efficiency and reliability of *** structural geometry design and layout optimization of radiators is promising to improve the heat dissipation efficiency and reduce aerodynamic *** purpose of this study is to investigate the state of the art and perspectives of aeroengine radiator structural design by a comprehensive literature *** main contents involve the review on the structural design and layout optimization technologies of radiator structures,the analyses of the structural features,design theory and methods of existed radiator structures,the induction of the theory and method of different radiators structural opti-mization design,and the discussion on the application perspectives of advanced structures in aeroengine radiators,the report on the current challenges and development directions of the design of radiator structures,including smart materials,lattice structures,variable structures,advanced optimization theories and methods,heat dissipation methods and so *** efforts of this study are promising to support the high-performance and lightweight design of aeroengine structures besides radiators,and thermal management system.

关键词： Aeroengine Radiator structure Smart structure Structure design Advanced materials

Application of fecal immunochemical test in colorectal cancer screening:A community-based,cross-sectional study in averagerisk individuals in Hainan

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3445-3456页

作者： Fan Zeng Da-Ya Zhang Shi-Ju chen Run-Xiang chen chen chen Shi-Mei Huang Da Li Xiao-Dong Zhang jia-jia chen Cui-Yi Mo Lei Gao Jun-Tao Zeng jian-Xin Xiong Zhai chen Fei-Hu Bai Graduate School Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Department of Gastroenterology Qionghai People’s HospitalQionghai 571400Hainan ProvinceChina Department of Gastroenterology Sanya Central HospitalSanya 572022Hainan ProvinceChina Department of Gastroenterology Hainan Second People’s HospitalWuzhishang 572299Hainan ProvinceChina Department of Gastroenterology Dongfang People’s HospitalDongfang 572699Hainan ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Hainan Medical UniversityHaikou 570216Hainan ProvinceChina The Gastroenterology Clinical Medical Center of Hainan Province Haikou 570216Hainan ProvinceChina

BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage *** highlights the significance of early detection and prevention measures to enhance survival *** immunochemical testing(FIT)is a globally recommended CRC screening method;however,limited research has been conducted on its application in *** To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan,while also examining the risk factors associated with positive FIT *** This population-based cross-sectional study implemented FIT screening for CRC in 2.00 asymptomatic participants aged 40-75 years from five cities and 2. community health centers in Hainan *** study was conducted from August 2.2. to April 2.2.,employing a stratified sampling method to select *** with positive FIT results subsequently underwent *** predictive values for confirmed CRC and advanced adenoma were calculated,and the relationship between relevant variables and positive FIT results was analyzed usingχ2.tests and multivariate logistic *** A total of 1788 participants completed the FIT screening,with a median age of 57 years(interquartile range:40-75).Among them,503(2..1%)were males,and 12.5(71.9%)were females,resulting in an 89.4%compliance rate for FIT *** overall positivity rate of FIT was 4.4%[79 out of 1788;95%confidence interval(CI):3%-5%].The specific positivity rates for Haikou,Sanya,Orient City,Qionghai City,and Wuzhishan City were 9.6%(45 of 468;95%CI:8%-11%),1.3%(6 of 445;95%CI:0.1%-3.1%),2.7%(8 of 2.3;95%CI:1.2.-4.3%),3.3%(9 of 2.6;95%CI:1.0%-6.3%),and 4.2.(11 of 406;95%CI:1.2.-7.3%),*** associations were found between age,dietary habits,and positive FIT *** of the 79 participants with positive FIT results,55 underwent colonoscopy,demonstrating an 82.2.compliance *** them,10 had a clean

关键词： Fecal immunochemical test Colorectal cancer Adenoma Screening Hainan Province

EuSHT Acts as a Hub Gene Involved in the Biosynthesis of 6-Hydroxyluteolin and Quercetin Induced by Salt Stress in Eucommia ulmoides

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 2095-2113页

作者： Fuxin Li Enyan chen Xinxin chen Jingyu {2. Hemin Wang Jie Zhang {2.nrui Sun Xin Li College of Food and Bioengineering Henan University of Science and TechnologyLuoyang471023China Henan Engineering Research Center of Food Microbiology Luoyang471023China National Demonstration Center for Experimental Food Processing and Safety Education Luoyang471000China

Salt stress inhibits plant growth and affects the biosynthesis of its secondary *** are natural compounds that possess many important biological activities,playing a significant role in the medicinal activity of Eucommia ulmoides(***).To investigate the mechanism by which salt stress affects the biosynthesis of flavonoids in ***,a comprehensive analysis of metabolomics and transcriptomics was *** results indicated that salt stress led to the wilting and darkening of *** leaves,accompanied by a decrease in chlorophyll levels,and significantly induced malondialdehyde(MDA)and relative electrical *** salt stress,most metabolites in the flavonoid biosynthesis pathway of *** were upregulated,indicating that flavonoid biosynthesis is likely the main induced pathway under salt *** them,secondary metabolites such as 6-Hydroxyluteolin and Quercetin are likely key metabolites induced by salt *** correlation analysis of transcriptomics and metabolomics revealed that EuSHT is a hub gene induced by salt stress,promoting the production of flavonoids such as *** co-expression network showed a strong positive correlation between EuSHT and the biosynthesis of 6-Hydroxyluteolin and Quercetin,while it exhibited a negative correlation with Catechin *** branches leading to Luteolin and Dihydroquercetin are likely the main pathways for flavonoid compound biosynthesis in the plant stress response during salt *** results of this study provided a preliminary mechanism of secondary metabolites such as flavonoids in the medicinal plant *** induced by salt stress and provided new theoretical support for discussing the mechanism of plant stress *** also provided useful information for subsequent exploration of resistance genes in ***.

关键词： Eucommia ulmoides ﬂavonoid salt stress transcriptomics widely targeted metabolomics

Multi-Scale Mixed Attention Tea Shoot Instance Segmentation Model

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 261-275页

作者： Dongmei chen Peipei Cao Lijie Yan Huidong chen {2. Lin Xin Li Lin Yuan Kaihua Wu School of Automation Hangzhou Dianzi UniversityHangzhou310018China Tea Research Institute Chinese Academy of Agriculture SciencesHangzhou310018China School of Information Engineering Zhejiang University of Water Resources and Electric PowerHangzhou310018China

Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the *** tea-picking machines may compromise the quality of the tea ***-quality teas are often handpicked and need more delicate operations in intelligent picking *** with traditional image processing techniques,deep learning models have stronger feature extraction capabilities,and better generalization and are more suitable for practical tea shoot ***,current research mostly focuses on shoot detection and cannot directly accomplish end-to-end shoot segmentation *** propose a tea shoot instance segmentation model based on multi-scale mixed attention(Mask2.usionNet)using a dataset from the tea garden in *** further analyzed the characteristics of the tea shoot dataset,where the proportion of small to medium-sized targets is 89.9%.Our algorithm is compared with several mainstream object segmentation algorithms,and the results demonstrate that our model achieves an accuracy of 82.in recognizing the tea shoots,showing a better performance compared to other *** ablation experiments,we found that ResNet50,PointRend strategy,and the Feature Pyramid Network(FPN)architecture can improve performance by 1.6%,1.4%,and 2.4%,*** experiments demonstrated that our proposed multi-scale and point selection strategy optimizes the feature extraction capability for overlapping small *** results indicate that the proposed Mask2.usionNet model can perform the shoot segmentation in unstructured environments,realizing the individual distinction of tea shoots,and complete extraction of the shoot edge contours with a segmentation accuracy of 82.0%.The research results can provide algorithmic support for the segmentation and intelligent harvesting of premium tea shoots at different scales.

关键词： Tea shoots attention mechanism multi-scale feature extraction instance segmentation deep learning

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-Dong Zhang Dong-Ting Gao Gang Liu Chun-Hai chen jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2.Cl_(2.).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2.Cl_(2. in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2.Cl_(2. in PAEK films were observed to decrease with increasing *** effect of CH_(2.Cl_(2.absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2.Cl_(2. has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

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Novel C_(sf)/SiBCN composites prepared by densifying C_(sf)/MA-SiBCN with the PIP process:Oxidation behavior and damage mechanism

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Journal of Advanced Ceramics 2024年第5期13卷 666-678页

作者： Wenhao Dou Daxin Li Bingzhu Wang Zhihua Yang Jun chen Dechang jia Ralf Riedel Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structural-Functional Integration Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China Chongqing Research Institute of HIT Chongqing 401135China Beijing Institute of Control Engineering Beijing 100094China Institut für Materialwissenschaft Technische Universität DarmstadtDarmstadt D-64287Germany School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

To improve the oxidation resistance of short carbon fiber(C_(sf))-reinforced mechanically alloyed SiBCN(MA-SiBCN)(C_(sf)/MA-SiBCN)composites,dense amorphous C_(sf)/SiBCN composites containing both MA-SiBCN and polymer-derived ceramics SiBCN(PDCs-SiBCN)were prepared by repeated polymer infiltration and pyrolysis(PIP)of layered C_(sf)/MA-SiBCN composites at 1100℃,and the oxidation behavior and damage mechanism of the as-prepared C_(sf)/SiBCN at 1300–1600℃ were compared and discussed with those of C_(sf)/*** C_(sf)/MA-SiBCN composites resist oxidation attack up to 1400℃ but fail at 1500℃ due to the collapse of the porous framework,while the PIP-densified C_(sf)/SiBCN composites are resistant to static air up to 1600℃.During oxidation,oxygen diffuses through preexisting pores and the pores left by oxidation of carbon fibers and pyrolytic carbon(PyC)to the interior of the *** to the oxidative coupling effect of the MA-SiBCN and PDCs-SiBCN matrices,a relatively continuous and dense oxide layer is formed on the sample surface,and the interfacial region between the oxide layer and the matrix of the as-prepared composite contains an amorphous glassy structure mainly consisting of Si and O and an incompletely oxidized but partially crystallized matrix,which is primarily responsible for improving the oxidation resistance.

关键词： mechanically alloyed SiBCN(MA-SiBCN) polymer-derived ceramics SiBCN(PDCs-SiBCN) short carbon fiber-reinforced SiBCN(C_(sf)/SiBCN)composites polymer infiltration and pyrolysis(PIP) oxidation damage mechanism

In situ observation of the electrochemical behavior of Li–CO_(2./O_(2.batteries in an environmental transmission electron microscope

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Carbon Energy 2024年第4期6卷 244-255页

作者： Peng jia Yunna Guo Dongliang chen Jingming Yao Xuedong Zhang jianguo Lu Yuqing Qiao Liqiang Zhang Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdaoChina State Key Laboratory of Metastable Materials Science and Technology Clean Nano Energy CenterYanshan UniversityQinhuangdaoChina State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang UniversityHangzhouChina Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtanChina

Li–CO_(2./O_(2.batteries,a promising energy storage technology,not only provide ultrahigh discharge capacity but also capture CO_(2.and turn it into renewable *** electrochemical reaction pathways'ambiguity,however,creates a hurdle for their practical *** study used copper selenide(CuSe)nanosheets as the air cathode medium in an environmental transmission electron microscope to in situ study Li–CO_(2./O_(2.(mix CO_(2.as well as O_(2.at a volume ratio of 1:1)and Li–O_(2.batteries as well as Li–CO_(2.*** discharge reactions take place successively in the Li–CO_(2./O_(2.–CuSe nanobattery:(I)4Li^(+)+O_(2.+4e^(−)→2.i_(2.O;(II)Li_(2.O+CO_(2.→Li_(2.CO_(3).The charge reaction proceeded via(III)2.i_(2.CO_(3)→4Li^(+)+2.O_(2.+O_(2.+4e^(−).However,Li–O_(2.and Li–CO_(2.nanobatteries showed poor cycling stability,suggesting the difficulty in the direct decomposition of the discharge *** fluctuations of the Li–CO_(2./O_(2.battery's electrochemistry were also shown to depend heavily on O_(2..The CuSe‐based Li–CO_(2./O_(2.battery showed exceptional electrochemical *** Li^–CO_(2./O_(2.battery offered a discharge capacity apex of 15,492.mAh g^(−1) and stable cycling 60 times at 100 mA g^(−1).Our research offers crucial insight into the electrochemical behavior of Li–CO_(2./O_(2.,Li–O_(2.,and Li–CO_(2.nanobatteries,which may help the creation of high‐performance Li–CO_(2./O_(2.batteries for energy storage applications.

关键词： CuSe nanosheets electrochemical reaction in situ environmental transmission electron microscopy Li-CO_(2.battery Li-CO_(2./O_(2.battery Li-O_(2.battery

Bending Failure Mode and Prediction Method of the Compressive Strain Capacity of A Submarine Pipeline with Dent Defects

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China Ocean Engineering 2024年第4期38卷 636-647页

作者： HOU Fu-heng jia Lu-sheng chen Yan-fei ZHANG Qi ZHONG Rong-feng WANG Chun-sha School of Mechanical and Transportation Engineering China University of PetroleumBeijingBeijing 102249China CNOOC Research Institute Ltd.Beijing 10002. China

A dent is a common type of defects for submarine *** submarine pipelines,high hydrostatic pressure and internal pressure are the main *** pipelines bend due to complex subsea conditions,the compression strain capacity may be *** into the local buckling failure and accurate prediction of the compressive strain capacity are important.A finite element model of a pipeline with a dent is *** buckling failure under a bending moment is investigated,and the compressive strain capacity is *** effects of different parameters on pipeline local buckling are *** results show that the dent depth,external pressure and internal pressure lead to different local buckling failure modes of the pipeline.A higher internal pressure indicates a larger compressive strain capacity,and the opposite is true for external *** the ratio of external pressure to collapse pressure of intact pipeline is greater than 0.1,the deeper the dent,the greater the compressive strain capacity of the *** as the ratio is less than 0.1,the opposite is *** the basis of these results,a regression equation for predicting the compressive strain capacity of a dented submarine pipeline is proposed,which can be referred to during the integrity assessment of a submarine pipeline.

关键词： submarine pipeline dent defect bending load local buckling compressive strain capacity

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Applicability and improvement of different potential evapotranspiration models in different climate zones of China

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Ecological Processes 2024年第1期13卷 262-282页

作者： Zedong Li Yiran Li Xinxiao Yu Guodong jia Peng chen Pengfei Zheng Yusong Wang Bingbing Ding Key Laboratory of Soil & Water Conservation and Desertification Combating of Ministry of Education Beijing Forestry University College of Horticulture and Forestry Sciences Tarim University State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Background Accurate estimation of potential evapotranspiration(PET) is the key for studying land-air interaction hydrological processes. Several models are used to estimate the PET based on standardized meteorological data. Although combination-based models have the highest level performance estimation of PET, they require more meteorological data and may therefore be difficult to apply in areas lacking meteorological observation *** The results showed significant differences in the spatial trends of PET calculated by different models in China, the Doorenbots–Pruitts model revealed the highest PET(1902.6 mm), and the Kuzmin model revealed the lowest PET(349.6 mm), with the largest difference being 5.5 times. The Romanenko and the Rohwer models were the recommended temperature-based and aerodynamic-based models. On the other hand, the Abtew model was more suitable for arid and semi-arid regions, while the Priestley–Taylor model was more suitable for humid regions. Combination-based models revealed ideal calculation accuracies, among which the Penman–Monteith model was the best option for PET *** The accuracy range of Romanenko, Rohwer, Abten, Priestley Taylor, and Penman Monteith models improved in MPZ and TCZ is higher than that improved in TMZ and SMZ. This does not mean that the improved models have higher accuracy in MPZ and TCZ than in TMZ and SMZ. On the contrary, the original model performed poorly in MPZ and TCZ, so the improved accuracy was relatively large. The unimproved model was already more suitable in TMZ and SMZ, so the improved accuracy was relatively small. Therefore, regional calibration of the PET models can improve the accuracy and applicability of PET calculation, providing a reference for studying hydrological processes in different climatic zones.

关键词： Potential evapotranspiration Climatic zone Temperature-based model Aerodynamic-based model Radiation-based model Combination-based model Model calibration